Migration of human mesenchymal stem cells stimulated with pulsed electric field and the dynamics of the cell surface glycosylation.

Background: The analysis of the stem cells' glycome dynamics at different stages of differentiation and migration makes possible the exploration of the cell surface glycans as markers of the stem cell functional status, and, in the future, compatibility between transplanted cell and host environment.

Objectives: The objective of our study was to develop novel techniques of investigating cell motility and to assess whether the electric field of the therapeutic spinal cord stimulation system used in vivo contributes to the migration of human mesenchymal stem cells (hMSCs) in vitro.

Material And Methods: We have investigated the electrotaxis of bone marrow-derived MSCs using pulsed electric field (PEF) in the range of 16-80 mV/mm and the frequency of 130 Hz and 240 Hz.

An Automated Confocal Micro-Extensometer Enables in Vivo Quantification of Mechanical Properties with Cellular Resolution.

How complex developmental-genetic networks are translated into organs with specific 3D shapes remains an open question. This question is particularly challenging because the elaboration of specific shapes is in essence a question of mechanics. In plants, this means how the genetic circuitry affects the cell wall.

Measuring the mechanical properties of plant cells by combining micro-indentation with osmotic treatments.

Growth in plants results from the interaction between genetic and signalling networks and the mechanical properties of cells and tissues. There has been a recent resurgence in research directed at understanding the mechanical aspects of growth, and their feedback on genetic regulation. This has been driven in part by the development of new micro-indentation techniques to measure the mechanical properties of plant cells in vivo.

Glycomics, extracellular matrix, and anti-glycan antibodies in exfoliation syndrome.

Exfoliation syndrome (XFS) is considered to be a disease of extracellular matrix. Here we review key experimental evidence of aberrations in structure, expression, and function of glycoproteins, complex carbohydrates, and glycosaminoglycans found in extracellular matrix components forming exfoliation material in patients presenting with XFS. We hypothesize that certain components of the accumulating exfoliation material can become immunogenic, and multiple natural antibodies or autoantibodies are generated.

The glycosphingolipid P₁ is an ovarian cancer-associated carbohydrate antigen involved in migration.

Background: The level of plasma-derived naturally circulating anti-glycan antibodies (AGA) to P1 trisaccharide has previously been shown to significantly discriminate between ovarian cancer patients and healthy women. Here we aim to identify the Ig class that causes this discrimination, to identify on cancer cells the corresponding P1 antigen recognised by circulating anti-P1 antibodies and to shed light into the possible function of this glycosphingolipid.

Methods: An independent Australian cohort was assessed for the presence of anti-P1 IgG and IgM class antibodies using suspension array.

Plasma Anti-Glycan Antibody Profiles Associated with Nickel level in Urine.

Nickel (Ni) compounds are widely used in industrial and commercial products including household and cooking utensils, jewelry, dental appliances and implants. Occupational exposure to nickel is associated with an increased risk for lung and nasal cancers, is the most common cause of contact dermatitis and has an extensive effect on the immune system. The purpose of this study was two-fold: (i) to evaluate immune response to the occupational exposure to nickel measured by the presence of anti-glycan antibodies (AGA) using a new biomarker-discovery platform based on printed glycan arrays (PGA), and (ii) to evaluate and compile a sequence of bioinformatics and statistical methods which are specifically relevant to PGA-derived information and to identification of putative "Ni toxicity signature".

Cross-platform comparison of glycan microarray formats.

Carbohydrates participate in almost every aspect of biology from protein sorting to modulating cell differentiation and cell-cell interactions. To date, the majority of data gathered on glycan expression has been obtained via analysis with either anti-glycan antibodies or lectins. A detailed understanding of the specificities of these reagents is critical to the analysis of carbohydrates in biological systems.

Natural Antibodies Against Sialoglycans.

Natural antibodies, part of the innate immunity system, are produced at strictly regulated levels in normal sera without immunization and thus are part of the innate immune system. The best studied natural antibodies are those directed against blood group antigens A and B and xeno-antigens including glycolylneuraminic acid containing Hanganutziu-Deicher (HD) glycolipid. Abnormal levels of anti-glycan antibodies were found in a number of pathologies.

Fibulin-3 as a blood and effusion biomarker for pleural mesothelioma.

Background: New biomarkers are needed to detect pleural mesothelioma at an earlier stage and to individualize treatment strategies. We investigated whether fibulin-3 in plasma and pleural effusions could meet sensitivity and specificity criteria for a robust biomarker.

Methods: We measured fibulin-3 levels in plasma (from 92 patients with mesothelioma, 136 asbestos-exposed persons without cancer, 93 patients with effusions not due to mesothelioma, and 43 healthy controls), effusions (from 74 patients with mesothelioma, 39 with benign effusions, and 54 with malignant effusions not due to mesothelioma), or both.

Repertoire of human natural anti-glycan immunoglobulins. Do we have auto-antibodies?

Background: Profiling of donor's antibodies using glycan arrays demonstrated presence of antibodies capable of binding to >100 mammalian glycans or their fragments. For example, relatively high binding to Galα1-4Galβ1-4GlcNAc (P(1)), Galα1-4Galβ1-4Glc (P(k)), Galβ1-3GlcNAc (Le(c)), 4-O-SuGalβ1-4GlcNAc, and GalNAcα1-3GalNAc (Fs) was found in all tested individuals. Affinity isolation using hapten-specific chromatography in combination with epitope mapping revealed their glycotopes.

Processing and analysis of serum antibody binding signals from Printed Glycan Arrays for diagnostic and prognostic applications.

Procedures for data preprocessing, quality control, data analysis, evaluation and visualization of the new high-throughput biomarker platform based on printed glycan arrays (PGA) are presented in this paper. PGAs are similar in concept to DNA arrays but contain deposits of various carbohydrate structures (glycans) instead of spotted DNAs. PGA biomarker discovery for the early detection, diagnosis and prognosis of human malignancies and viral diseases is based on the response of the immune system as measured by the level of binding of anti-glycan antibodies from human serum to the glycans on the array.

Changes in the repertoire of natural antibodies caused by immunization with bacterial antigens.

The repertoire of natural anti-glycan antibodies in naïve chickens and in chickens immunized with bacteria Burkholderia mallei, Burkholderia pseudomallei, and Francisella tularensis as well as with peptides from an outer membrane protein of B. pseudomallei was studied. A relatively restricted pattern of natural antibodies (first of all IgY against bacterial cell wall peptidoglycan fragments, L-Rha, and core N-acetyllactosamine) shrank and, moreover, the level of detectable antibodies decreased as a result of immunization.

Comparison of printed glycan array, suspension array and ELISA in the detection of human anti-glycan antibodies.

Anti-glycan antibodies represent a vast and yet insufficiently investigated subpopulation of naturally occurring and adaptive antibodies in humans. Recently, a variety of glycan-based microarrays emerged, allowing high-throughput profiling of a large repertoire of antibodies. As there are no direct approaches for comparison and evaluation of multi-glycan assays we compared three glycan-based immunoassays, namely printed glycan array (PGA), fluorescent microsphere-based suspension array (SA) and ELISA for their efficacy and selectivity in profiling anti-glycan antibodies in a cohort of 48 patients with and without ovarian cancer.

Detection of integrin-linked kinase in the serum of patients with malignant pleural mesothelioma.

Objective: Integrin-linked kinase, which is relevant to neoplastic transformation, is highly expressed in malignant pleural mesothelioma. Recently, detection of integrin-linked kinase in serum of patients with ovarian cancer has been reported. This study asks whether integrin-linked kinase can also be detected in serum of patients with malignant pleural mesothelioma and whether serum level has diagnostic or prognostic relevance for that disease.

Serum antiglycan antibody detection of nonmucinous ovarian cancers by using a printed glycan array.

Epithelial ovarian cancer has the highest mortality rate among gynecological cancers. Altered glycosylation is associated with oncogenic transformation producing tumor-associated carbohydrate antigens. We investigated the potential of natural occurring antiglycan antibodies in the diagnosis of ovarian cancer by using printed glycan array.

Anti-carbohydrate antibodies of normal sera: findings, surprises and challenges.

We have used microchip format glycan array to characterize the individual carbohydrate recognition patterns by antibodies (Ab) in sera of 106 healthy donors. The glycan library included blood group antigens and other most frequent terminal oligosaccharides and their cores of mammalian N- and O-linked glycoproteins and glycolipids, tumor-associated carbohydrate antigens, and common components of bacterial/pathogenic polysaccharides and lipopolysaccharides, totally 205 glycans. The serum Ab interacted with at least 50 normal human glyco-motifs.

Reliable motion artifact detection for ECG monitoring systems with dry electrodes.

Reliable signals are the basic prerequisite for most mobile ECG monitoring applications. Especially when signals are analyzed automatically, capable motion artifact detection algorithms are of great importance. This article presents different artifact detection algorithms for ECG systems with dry electrodes.

Endogenous galectin-1 enforces class I-restricted TCR functional fate decisions in thymocytes.

During thymocyte development, the T-cell receptor (TCR) can discriminate major histocompatibility complex (MHC)/peptide ligands over a narrow range of affinities and translate subtle differences into functional fate decisions. How small differences in TCR input are translated into absolute differences in functional output is unclear. We examined the effects of galectin-1 ablation in the context of class-I-restricted thymocyte development.

2-Aminopyridine--a label for bridging of oligosaccharides HPLC profiling and glycoarray printing.

2-Aminopyridine derivatives of oligosaccharides (OS-AP) were printed onto microchips by two different ways. The first method is based on direct covalent insertion of OS-AP in polyacrylamide gel 3D chip. The second method is based on conversion of OS-AP into more reactive OS-aminoalditol followed by covalent printing onto NHS-activated glass slides.

Printed covalent glycan array for ligand profiling of diverse glycan binding proteins.

Here we describe a glycan microarray constructed by using standard robotic microarray printing technology to couple amine functionalized glycans to an amino-reactive glass slide. The array comprises 200 synthetic and natural glycan sequences representing major glycan structures of glycoproteins and glycolipids. The array has remarkable utility for profiling the specificity of a diverse range of glycan binding proteins, including C-type lectins, siglecs, galectins, anticarbohydrate antibodies, lectins from plants and microbes, and intact viruses.

Fluorescence polarization as an analytical tool to evaluate galectin-ligand interactions.

Galectins are a family of beta-galactose binding lectins associated with functions such as immunological and malignant events. To study the binding affinity of galectins for natural and artificial saccharides and glycoconjugates we have developed an assay using fluorescence polarization. A collection of fluorescein-conjugated saccharides was synthesized and used as probes with galectins-1 and -3 and the two carbohydrate recognition domains of galectin-4.

Galectin-4 in normal tissues and cancer.

Galectin-4 belongs to a subfamily of galectins composed of two carbohydrate recognition domains within the same peptide chain. The two domains have all the conserved galectin signature amino acids, but their overall sequences are only approximately 40% identical. Both domains bind lactose with a similar affinity as other galectins, but their respective preferences for other disaccharides, and larger saccharides, are distinctly different.

Galectin-3 binds lactosaminylated lipooligosaccharides from Neisseria gonorrhoeae and is selectively expressed by mucosal epithelial cells that are infected.

Galectins are a family of beta-galactoside binding proteins that have been proposed as host receptors for bacteria because beta-galactoside carbohydrates are common in bacterial membrane glycolipid lipooligosaccharides (LOS) and lipopolysaccharides. We investigated the interaction of galectin-3 with gonococcal LOS that make lactosyl (Lc2 or Lac), paraglobosyl (nLc4; LNnT; lacto-N-neotetraose), gangliosyl (IV3GalNAcnLc4), and neolactohexaosyl (nLc6, lactonorhexaosyl) oligosaccharides. All but gangliosyl LOS terminate in beta-galactoside.

Regulation of mucosal immune responses by recombinant interleukin 10 produced by intestinal epithelial cells in mice.

Background & Aims: Interleukin (IL)-10 is a cytokine with anti-inflammatory properties. The aim of this study was to explore the effect of a site-specific delivery of IL-10 on intestinal immune responses.

Methods: Transgenic mice were created in which IL-10 is expressed by the intestinal epithelial cells.